213261525137 has 4 divisors (see below), whose sum is σ = 213262511616. Its totient is φ = 213260538660.

The previous prime is 213261525119. The next prime is 213261525193. The reversal of 213261525137 is 731525162312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 213261525137 - 2⁸ = 213261524881 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 213261525137.

It is not an unprimeable number, because it can be changed into a prime (213261545137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13289 + ... + 653222.

It is an arithmetic number, because the mean of its divisors is an integer number (53315627904).

Almost surely, 2^213261525137 is an apocalyptic number.

It is an amenable number.

213261525137 is a deficient number, since it is larger than the sum of its proper divisors (986479).

213261525137 is an equidigital number, since it uses as much as digits as its factorization.

213261525137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986478.

The product of its digits is 75600, while the sum is 38.

Adding to 213261525137 its reverse (731525162312), we get a palindrome (944786687449).

The spelling of 213261525137 in words is "two hundred thirteen billion, two hundred sixty-one million, five hundred twenty-five thousand, one hundred thirty-seven".